Learning Progressions And Practical Research On �Chemical Bonds�

In 2004,Smith and others officially proposed the Learning progressions.Later,the researchers applied the theory of �Learning progressions� to teaching research,which has an important influence on the preparation of curriculum standards,curriculum design and classroom teaching.In 2017,China's "Chemistry Curriculum Standards for Senior High Schools" embodies the research idea of the Learning progressions.It divides the core literacy into four levels,which provides a reference for the formulation of teaching objectives and evaluation goals at each stage.It can be seen that the teaching practice based on the Learning progressions is also very important.Learning progressions provides a basis for effective teaching of teachers.Learning progressions focuses on the development of students' knowledge and abilities,promotes effective learning,and implements the development of students' core literacy.In addition,there are some problems in the teaching practice of "chemical bonds"."Chemical bonds" involve a variety of basic concepts of chemistry,knowledge abstraction,complex classification and other factors lead to a large thinking span for understanding chemical bonds.In the teaching,the teacher's grasp of the teaching and evaluation objectives of the �chemical bond� knowledge at various stages is uneven,and there is no overall planning.In order to solve these problems,this thesis uses learning to build Learning progressions of "chemical bonds" and apply Learning progressions concepts in teaching practice.Firstly,through the literature review,the advanced domestic and foreign literatures were studied,and the Learning progressions and core concepts were defined.Secondly,this paper refers to the Luke version of chemistry textbooks,chemistry curriculum standards,college entrance examination syllabus and advanced literature on learning,the teaching analysis of "chemical bond" knowledge,analysis of the characteristics of "chemical bond" knowledge and problems in teaching,The Learning progressions of �chemical bond� based on the advanced concept of learning was constructed.The advanced level of chemical bonds is divided according to the school segment,and the expected level of students and the level of student understanding at each stage are established.Finally,the teaching practice of this paper is based on the knowledge of chemical bond in the second stage of chemistry.The design is based on the teaching design of the Learning progressions concept and implements the development of students' core literacy.At the same time,the experimental class and the control class are set up;the experimental class is taught according to the teaching plan based on the Learning progressions concept,and the control class is taught according to the traditional teaching plan.Conduct pre-tests before teaching practice to understand the knowledge base of students.Post-testing and questionnaire surveys are conducted after the teaching practice to trace the students' knowledge development and students' learning experiences.Through research,it is found that:(1)The Learning progressions of "chemical bond" is constructed.The knowledge of chemical bonds is sorted out,and the characteristics of chemical bond knowledge content and problems in teaching are analyzed.The chemical bond learning in the entire high school stage is divided into 6 segments,and the chemical bonds are divided into 6 advanced levels according to the segment.The advanced construction of �Chemical Bonds� can help teachers to clarify the advanced starting point and advanced goals of each syllabus,avoiding blindly increasing the difficulty of teaching during the teaching process,and causing students to lose interest in chemistry learning.(2)Applying the Learning progressions concept to teaching practice can promote students' efficient learning.Set up the control class and the experimental class,conduct pre-test before teaching,understand the knowledge base of the two classes,and carry out teaching practice.The control class uses the traditional teaching program,and the experimental class adopts a teaching plan based on the Learning progressions concept: Use the Learning progressions concept to analyze the situation,plan the advanced process of each lesson,and design specific learning tasks to help students complete the advanced knowledge of chemical bonds.After the teaching practice,the post-test and student interviews were used to test the teaching effect of the two classes.The comparison showed that the experimental class had better teaching effect,that is the teaching based on the Learning progressions concept can promote the effective teaching of the teachers and the efficient learning of the students.